Now showing items 1-15 of 15

    • 45 GHz bandwidth-efficiency resonant cavity enhanced ITO-Schottky photodiodes 

      Bıyıklı, Necmi; Kimukin, İbrahim; Aytür, Orhan; Özbay, Ekmel; Gökkavas, M.; Ünlü, M. S. (OSA, 2001)
      We demonstrated high-performance resonant cavity enhanced ITO-Schottky photodiodes. We achieved a peak efficiency of 75% around 820 nm with a 3-dB bandwidth of 60 GHz resulting in a bandwidth-efficiency product of 45 GHz.
    • Advances in femtosecond single-crystal sum-frequency generating optical parametric oscillators 

      Köprülü, Kahraman G.; Kartaloğlu, Tolga; Dikmelik, Yamaç; Aytür, Orhan (IEEE, 1998)
      The effect of compensating the group velocity mismatch between the orthogonal pump components on the conversion efficiency of the optical parametric oscillators (OPOs) was investigated. A femtosecond single-crystal ...
    • High-performance ALGaN-based visible-blind resonant cavity enhanced Schottky photodiodes 

      Kimukin, İbrahim; Bıyıklı, Necmi; Kartaloğlu, Tolga; Aytür, Orhan; Özbay, Ekmel (Materials Research Society, 2003-04)
      We have designed, fabricated and tested resonant cavity enhanced visible-blind AlGaN-based Schottky photodiodes. The bottom mirror of the resonant cavity was formed with a 20 pair AlN/AlGaN Bragg mirror. The devices were ...
    • High-performance ITO-AlAs/GaAs based resonant cavity enhanced Schottky photodiodes 

      Özbay, Ekmel; Bıyıklı, Necmi; Kimukin, İbrahim; Aytür, Orhan (IEEE, 1999)
      The fabrication of ITO (indium tin oxide)-AlAs-based resonant cavity enhanced Schottky photodiodes was examined. The device structure was designed to achieve a low-loss cavity around a 840 nm optical communication window. ...
    • High-performance solar-blind AlGaN photodetectors 

      Özbay, Ekmel; Bıyıklı, Necmi; Kimukin, İbrahim; Tut, Turgut; Kartaloğlu, Tolga; Aytür, Orhan (IEEE, 2004)
      High-performance aluminum gallium nitride (AlGaN)-based solar-blind (SB) photodetectors were demonstrated using different device structures. The Al x-Ga1-xN layers structure were grown by metalorganic chemical vapor ...
    • High-speed 1.3 μm GaAs internal photoemission resonant cavity enhanced photodetector 

      Kimukin, İbrahim; Özbay, Ekmel; Bıyıklı, Necmi; Kartaloğlu, Tolga; Aytür, Orhan; Tuttle, G. (IEEE, 2000)
      Resonant cavity enhanced (RCE) photodetectors offer the possibility of overcoming the low quantum efficiency limitation of conventional photodetectors. The RCE detectors are based on the enhancement of the optical field ...
    • High-speed solar-blind AlGaN Schottky photodiodes 

      Bıyıklı, Necmi; Kimukin, İbrahim; Kartaloğlu, Tolga; Aytür, Orhan; Özbay, Ekmel (Cambridge University Press, 2003)
      We report high-speed solar-blind AlGaN-based Schottky photodiodes. AlGaN/GaN heterostructure device layers were grown on sapphire substrate. The devices were fabricated on AlGaN/GaN heterostructuresusing a microwave ...
    • High-speed solar-blind AlGaN-based metal-semiconductor-metal photodetectors 

      Bıyıklı, Necmi; Kimukin, İbrahim; Kartaloğlu, Tolga; Aytür, Orhan; Özbay, Ekmel (Wiley, 2003)
      Solar-blind AlGaN metal-semiconductor-metal (MSM) photodetectors with fast pulse response have been demonstrated. The devices were fabricated on MOCVD-grown epitaxial Al0.38Ga0.62N layers, using a microwave compatible ...
    • High-speed visible-blind GaN-based ITO-Schottky photodiodes 

      Bıyıklı, Necmi; Kimukin, İbrahim; Kartaloğlu, Tolga; Aytür, Orhan; Özbay, Ekmel (SPIE, 2002)
      In this paper we present our efforts on the design, fabrication and characterization of high-speed, visible-blind, GaN-based ultra-violet (UV) photodiodes using indium-tin-oxide (ITO) Schottky contacts. ITO is known as a ...
    • High-speed widely-tunable >90% quantum-efficiency resonant cavity enhanced p-i-n photodiodes 

      Bıyıklı, Necmi; Kimukin, İbrahim; Aytür, Orhan; Gökkavas, M.; Ulu, G.; Mirin, R.; Christensen, D. H.; Ünlü, M. S.; Özbay, Ekmel (IEEE, 1998)
      Widely-tunable high-speed resonant cavity enhanced p-i-n photodiodes were designed, fabricated and tested for operation around 820 nm. The structure was grown by solid-source MBE on GaAs substrates and features high-reflectivity ...
    • Phase-matched self-doubling optical parametric oscillator 

      Kartaloğlu, Tolga; Köprülü, Kahraman G.; Aytür, Orhan (IEEE, 1996)
      A new self-doubling optical parametric oscillator (OPO) uses a single nonlinear crystal for both parametric generation and frequency doubling. It is based on a KTiOPO4 (KTP) crystal pumped by a Ti:Sapphire laser operating ...
    • Plane-wave dynamics of optical parametric oscillation with simultaneous sum-frequency generation 

      Akgün, Gülbin; Dikmelik, Yamaç; Aytür, Orhan (IEEE, 1998)
      The plane wave dynamics of a single-crystal upconversion optical parametric oscillators (OPO) with simultaneous sum-frequency generation (SFG) was studied. It was presumed that simultaneous phase-matching of the SFG and ...
    • A self-doubling optical parametric oscillator based on aperiodically-poled lithium niobate 

      Kartaloǧlu, Tolga; Figen, Ziya Gürkan; Aytür, Orhan (IEEE, 2001)
      A self-doubling optical parametric oscillator (SDOPO) having one-dimensional aperiodic grating structure based on a LiNbO3 crystal was constructed. The structure was designed to quasi-phase-match both second harmonic ...
    • Simultaneous optical parametric oscillation and sum-frequency generation within a single crystal for converting 1064 nm into 627 nm 

      Figen, Z. Gürkan; Aytür, Orhan (IEEE, 2005-07)
      We report a 1064-nm pumped optical parametric oscillator based on a single KTiOAsO4 crystal that simultaneously generates the sum frequency of the pump and signal wavelengths, providing a 627 nm output with a high conversion ...
    • Single-crystal sum-frequency generating optical parametric oscillator 

      Köprülü, Kahraman G.; Kartaloğlu, Tolga; Aytür, Orhan (IEEE, 1997)
      A sum-frequency generating optical parametric oscillator (OPO), where a single crystal is employed for both parametric oscillation and sum frequency generation, is presented. The OPO is based on a KTiOPO4 crystal that is ...